This invention relates to an Apparatus for upward and downward movement of an arm in a Robot system for taking out injection molded and die casting products.
The upward and downward movement of arms, particularly chucks, in a Robot system have hitherto been performed by a pneumatic cylinder. In the pneumatic cylinder, it is a problem that at both ends of a piston stroke a shock must be absorbed and the piston cannot be stopped at an intermediate position accurately. The arm is hitherto not satisfactorily controlled.
A piston rod of the pneumatic cylinder is loaded by gravity of members moved upwards and downwards. Since the load of the piston rod is unbalanced, it is difficult to absorb the shock at the stroke ends sufficiently.